A mystery electronic spy network apparently based in China has infiltrated hundreds of computers around the world and stolen files and documents, Canadian researchers have revealed.

The network, dubbed GhostNet, appears to target embassies, media groups, NGOs, international organisations, government foreign ministries and the offices of the Dalai Lama, leader of the Tibetan exile movement. The researchers, based at Toronto University's Munk Centre for International Studies, said their discovery had profound implications.

"This report serves as a wake-up call... these are major disruptive capabilities that the professional information security community, as well as policymakers, need to come to terms with rapidly," said researchers Ron Deibert and Rafal Rohozinski.

After 10 months of study, the researchers concluded that GhostNet had invaded 1,295 computers in 103 countries, but it appeared to be most focused on countries in south Asia and south-east Asia, as well as the Dalai Lama's offices in India, Brussels, London and New York. The network continues to infiltrate dozens of new computers each week.

Such a pattern, and the fact that the network seemed to be controlled from computers inside China, could suggest that GhostNet was set up or linked to Chinese government espionage agencies. However, the researchers were clear that they had not been able to identify who was behind the network, and said it could be run by private citizens in China or a different country altogether. A Chinese government spokesmen has denied any official involvement.